The time display system for related art portable terminal apparatus displays only the time in a specific area preset to the portable terminal apparatus. In case the portable terminal apparatus capable of international roaming has moved to an area to which communications are supported, the user has to set the time of his/her portable terminal apparatus in order to correctly display the time in the destination area each time a time difference is generated by the movement.
For example, the Japanese Patent Publication No. H4-119020 describes car telephone apparatus that receives an identification code representing the location of a base station and corrects time to be displayed based on the time difference registered in correspondence with the identification code in case the identification code has changed.
Further, the described car telephone apparatus issues an alarm when the car telephone apparatus has moved to an area where no identification codes are registered and registers a time difference by the user's input of a time difference corresponding to the destination area from the operation section, then corrects the displayed time based on the registered time difference.
However, in the time correction method via related art car telephone apparatus, etc., the user has to enter a time difference corresponding to the destination area when the user moves to an area where no identification codes are registered, that is, no time difference information is registered, even in case the area does not have a time difference, thus causing cumbersome time difference input work.
In case the user does not know the correct time difference information concerning the destination area when he/she has moved to an area where a time difference is not registered, the user cannot correct time properly.
In case the user wishes to know the time in a specific area except the area where the user is currently located, the user has to obtain the time via calculation based on the time difference between the area the user is currently located and the specific area.
The invention has been proposed in view of such a situation and aims at providing portable terminal apparatus that properly corrects time and displays the corrected time.